export default {
	// 为当前模块开启命名空间
	namespaced: true,

	// 模块的 state 数据
	state: () => ({
		// 购物车的数组，用来存储购物车中每个商品的信息对象
		// 每个商品的信息对象，都包含如下 6 个属性：
		// { goods_id, goods_name, goods_price, goods_count, goods_small_logo, goods_state }
		cart: JSON.parse(uni.getStorageSync('cart') || '[]'), //	从本地获取商品信息
	}),

	// 模块的 mutations 方法
	mutations: {
		addToCart(state, goods) { //	添加到购物车
			const findResult = state.cart.find(x => x.goods_id === goods.goods_id)
			if (!findResult) {
				state.cart.push(goods)
			} else {
				findResult.goods_count++
			}
			this.commit('m_cart/saveToStorage')
		},
		updateGoodsState(state, goods) { //	更新商品选中的状态
			const findResult = state.cart.find(x => x.goods_id === goods.goods_id)
			if (findResult) {
				findResult.goods_state = goods.goods_state
				this.commit('m_cart/saveToStorage')
			}
		},
		updateGoodsCount(state, goods) { //	更新商品数量
			const findResult = state.cart.find(x => x.goods_id === goods.goods_id)
			if (findResult) {
				findResult.goods_count = goods.goods_count
				this.commit('m_cart/saveToStorage')
			}
		},
		removeGoodsById(state, goods_id) { //	删除商品
			state.cart = state.cart.filter(x => x.goods_id !== goods_id)
			this.commit('m_cart/saveToStorage')
		},
		updateAllGoodsState(state, newState) { //	更新所有商品的勾选状态
			state.cart.forEach(x => x.goods_state = newState)
			this.commit('m_cart/saveToStorage')
		},
		saveToStorage(state) { //	把保存到购物车的商品信息保存到本地
			uni.setStorageSync('cart', JSON.stringify(state.cart))
		}
	},

	// 模块的 getters 属性
	getters: {
		total(state) { //	每一条商品的数量
			return state.cart.reduce((total, item) => total += item.goods_count, 0)
		},
		checkedCount(state) { //	购物车中所有商品的总数量
			return state.cart.filter(x => x.goods_state).reduce((total, item) => total += item.goods_count, 0)
		},
		checkedGoodsAmount(state) { //	已勾选商品的总价
			return state.cart.filter(x => x.goods_state).reduce((total, item) => total += item.goods_count * item.goods_price, 0).toFixed(2)
		},
	},
}
